为纪念中华人民共和国成立60周年,中国人民银行发行建国60周年金银纪念币一套。该套纪念币共5枚,其中金币3枚,银币2枚,均为中华人民共和国法定货币。该套纪念币①有价值和使用价值 ②在本质上是一般等价物 ③面值由社会必要劳动时间决定 ④价值是国家规定的,因为它是由国家发行的
---Can you work out the maths problem? ---Sorry, I can ______ understand its meaning.
--- Are you worried when your son often plays computer games? --- Yes. I think playing too many computer games ______ on teenagers.
I won’t watch TV ______ I finish my homework.
---______ to give the letter to Mr. Wang. It’s very important. ---No, I won’t.
On the 40th Earth Day, Dr Wang gave us a talk on the importance of ______ the earth.